The present invention relates to an apparatus for disposing an end of roving of a roving bobbin for intake of the roving end into the drafting device of a textile spinning machine and, more particularly, to an apparatus on a traveling service unit which is operable to perform a roving feed start operation.
European Patent Application No. 0 213 962 discloses a traveling service unit having an apparatus for disposing the roving end of a fresh roving bobbin at a location adjacent the drafting device of a textile spinning machine for piecing of the roving end with roving extending from another roving bobbin through the drafting device. The roving end disposing apparatus includes a generally V-shaped guide slot formed at its free end for guiding of the roving end therealong. An opening is formed in the side of the guide slot for directing air against the roving end disposed in the guide slot to ensure that the roving end remains in the guide slot during movement of the roving end disposing apparatus toward the disposing location. Once the roving end is disposed at the disposing location adjacent the roving already extending through the drafting device, piecing of the roving end is effected and roving is thereafter drawn from the fresh roving bobbin after severing of the roving supplied from the original roving bobbin.
However, a roving feed situation can arise in which there no roving present in the drafting device--e.g., the roving previously drafted through the drafting device has already been built on the package at the spinning station but roving has not continued to be drawn through the drafting device on account of, for example, the exhaustion of roving on the roving bobbin which had previously been supplying the spinning station or a break in the roving between the roving bobbin and the drafting device. Difficulties arise when a traveling service unit arrives at a spinning station at which the supply of roving has already been exhausted so that the roving no longer extends through the drafting device. At such spinning stations, it is no longer possible for the traveling service unit to piece a roving end from a fresh roving bobbin with roving extending through the drafting device and appropriate measures must then be undertaken to feed the roving end from the fresh roving bobbin into the drafting device.
Even on those textile spinning machines provided with a traveling service unit for responding to the upcoming exhaustion of roving from roving bobbins to exchange fresh roving bobbins therefor, the traveling service units of such spinning machines cannot reliably travel to each spinning station having a roving bobbin nearing exhaustion and, as a result, the roving may be completely exhausted at a spinning station before the traveling service unit arrives to exchange a fresh roving bobbin for the original roving bobbin. Although it is possible to control the movements of the traveling service unit to arrive at those spinning stations requiring fresh roving bobbins with sufficient lead time to ensure that the roving bobbins at such spinning stations are not yet exhausted, this solution is unsatisfactory since the traveling service unit may replace roving bobbins still having a relatively significant amount of roving thereon in order to travel in a timely manner to other spinning stations, thereby necessitating additional measures to handle the roving remaining on the replaced roving bobbins. Accordingly, the need exists for a method and apparatus which reliably disposes a roving end of a roving bobbin for reliable feeding of the roving end through a drafting device or reliable piecing of the roving end with roving from another roving bobbin.